1. Field of the Invention
This invention relates generally to boats and, more specifically, to a boat for alternatively operating in shallow water or at high speeds in deep water.
2. Background of the Prior Art
Various types of boats, ships or vessels have been used from the earliest recorded history of man. Different type boats have different functions. One boat may be designed for speed and another boat designed for hauling heavy loads. Likewise, boats may be designed for operation in shallow water versus deep water or in the ocean. Some boats are designed for maneuverability and others are designed for holding a straight line.
Fishing, whether as sport or as a means of making a living, is very popular throughout the world. While fishing can be performed from the banks, the best fishing is normally performed from boats operated either near the shore or in shallow water of bays or marshes which would normally have fish. To operate in such an environment, the boat should be maneuverable, but have the minimum amount of draft. Typically, some type of flat bottom boat best meets these requirements. However, getting to and from the good fishing areas from a suitable dock or put in location normally requires traveling some distance over open water. The traveling over open waters requires a boat having different characteristics than a boat that operates well in shallow waters. For example, to get to bays and inlets along the coast, it may be necessary to travel over open waters of the ocean or at least extended distances over inland ship channels. If the boat is designed entirely for shallow waters the time and efficiencies for traveling to and from various fishing points can be long and expensive.
It has been found that some type of hybrid between the shallow water boat and the deep water boat is necessary for most ideal conditions. One of the hybrid type boats that has been developed has been a tunnel-hull boat as shown in U.S. Pat. No. 6,125,781 by White. In White's tunnel-hull boat, a pointed bow is provided to cut through the waves when under way. A relatively flat bottom provides for a minimum draft to keep the motor from having to extend below the bottom of the boat when under way in shallow water. A tunnel is provided in the aft of the boat. The tunnel is straight and enlarging from the amidship to the aft of the boat. The tunnel draws water up to the propeller of the outboard motor when the boat is underway in shallow water as shown in White.
Further, White shows aeration with apertures to provide air at the beginning of the tunnel to reduce friction. However, the design as shown in White still has problems. The motor operates at the same depth in both shallow or deep water. Water is drawn up the tunnel when the boat is underway whether in shallow or deep water. The air being introduced at the entrance of the tunnel simply is used to reduce friction, not to cause separation between the water and the tunnel. The straight and enlarging design of the tunnel also does not induce separation of the water from the tunnel when operating at high speeds in deep water. A boat built in accordance with White never gets total separation between the water and tunnel even when the boat is operating at high speeds in open water.